ACST GMBH

Their core work

ACST GmbH is a German SME based in Hanau that develops terahertz (THz) semiconductor components, including resonant tunnelling diodes, terahertz sources, and detectors. They supply specialized hardware for THz communication systems, imaging, and sensing applications. Their work bridges electronics and photonics, providing the physical devices that enable ultra-high-bandwidth wireless links and THz instrumentation used across telecom, security, and scientific research.

What they specialise in

How they've shifted over time

ACST's earliest H2020 involvement (2017) focused narrowly on THz communication hardware for wireless networks through TERAPOD. By 2018-2020, they expanded into the broader THz device ecosystem — sources, detectors, and resonant tunnelling diodes via TeraApps — while their most recent project (TERAOPTICS, 2020) pivots toward integrated photonics, signaling a move from discrete components to on-chip photonic integration. The trajectory shows a company deepening from application-specific THz parts toward platform-level photonic integration.

ACST is moving from discrete THz components toward integrated photonic platforms, positioning them for next-generation 6G communication and multi-application THz systems.

How they like to work

ACST operates exclusively as a participant or third-party contributor, never as a coordinator — consistent with a specialist SME that provides critical hardware components rather than managing large research programmes. With 41 unique partners across 11 countries from just 3 projects, they work in large, diverse consortia (averaging ~14 partners per project). This suggests they are a sought-after component supplier that larger teams pull in for their niche THz device capabilities.

Despite only three projects, ACST has built a broad network of 41 partners across 11 countries, reflecting the wide European interest in THz technology. Their reach spans well beyond Germany, with connections across the EU research and industry landscape in photonics and communications.

What sets them apart

ACST is one of very few European SMEs that can actually manufacture terahertz semiconductor devices — most THz work stays in university labs. Their combination of resonant tunnelling diode expertise with integrated photonics capability makes them a rare industry partner for consortia that need real THz hardware, not just simulations. For any project requiring physical THz components — from 6G prototypes to security scanners — ACST fills a gap that academic partners alone cannot.

Highlights from their portfolio

• TERAOPTICS
  Their most recent and largest-funded project (EUR 252,788), extending THz photonics across five application domains including communications, space, and security — signaling strategic broadening.
• TERAPOD
  Focused on THz-based ultra-high-bandwidth wireless access networks, directly relevant to emerging 6G technology roadmaps.
• TeraApps
  A doctoral training network (MSCA-ITN) covering the full THz device stack — sources, detectors, and systems — indicating ACST's role in training the next generation of THz engineers.